Martel Electronics QM130M - Manual (Page 2)

WIRE FUNCTIONS
RED V+ Positive power supply connection.
BLACK 0V Negative power supply connection.
WHITE Vin Positive measuring input with reference to 0V.
Range from 0 to 1V d.c.
SAFETY
To comply with the Low Voltage Directive (LVD 93/68/EEC), input voltages to the module’s pins must not exceed 60Vdc. The user must
ensure that the incorporation of the unit into the user’s equipment conforms to the relevant sections of BS EN 61010 (Safety Requirements
for Electrical Equipment for Measuring, Control and Laboratory Use).
VARIOUS OPERATING MODES
Specifications liable to change without prior warning QM 130M Issue 8 September/2001 M.C. Applies to QM 130M
Measuring a d.c. current.
Rs =
I
1V
5...12Vd.c.
V+
Vin
0V
0V
Load
Rs
Power
Supply
Measuring a voltage in the range
0 to 1V d.c.
0-1Vd.c.
5...12Vd.c.
+
-
V+
Vin
0V
0V
Simultaneous d.c. Voltage and Current Measurement.
Rs =
I
1V
5...12Vd.c.
V+
V+
Vin
Vin
0V
0V
0V
Load
Rs
Rb
Ra
Power
Supply
I
Current
Voltage
V1 V2
+
-
Ra
Rb
Vin
0V
Voltage
Ra=1M
Rb=Ra.
V1-V2
V2 .
+
-
Rs
I
FSD
Vin
0V
Current
Rs=
I
1V
FSD
SCALING
Two external resistors may be used to alter the full scale
reading of the meter - see table for sample values.
Alternatively, use the following formulae to calculate Ra
and Rb. Select the nearest available standard resistor. To
achieve optimum accuracy, use 1% metal film resistors.
Required F.S.R. Ra Rb
10V 910k 100k
100V 1M 10k
10mA 0R 100R
100mA 0R 10R
Martel Electronics, Corp. P.O. Box 770 Londonderry, NH 03053
Toll Free: (800) 821-0023 Phone: (603) 434-1433 Fax: (603) 434-1653